Analysis of the VSX1 Gene in Sporadic Keratoconus Patients from China Tao Guan1†, Xue Wang2†, Li-Bin Zheng3, Hai-Jian Wu1 and Yu-Feng Yao3*

Total Page:16

File Type:pdf, Size:1020Kb

Analysis of the VSX1 Gene in Sporadic Keratoconus Patients from China Tao Guan1†, Xue Wang2†, Li-Bin Zheng3, Hai-Jian Wu1 and Yu-Feng Yao3* Guan et al. BMC Ophthalmology (2017) 17:173 DOI 10.1186/s12886-017-0567-3 RESEARCH ARTICLE Open Access Analysis of the VSX1 gene in sporadic keratoconus patients from China Tao Guan1†, Xue Wang2†, Li-Bin Zheng3, Hai-Jian Wu1 and Yu-Feng Yao3* Abstract Background: Keratoconus normally presents as a sporadic disease. Although different studies have found sequence variants of the visual system homeobox 1 (VSX1) gene associated with keratoconus in humans, no research has detected such variants in sporadic keratoconus patients from China. To investigate the possibility of VSX1 being a candidate susceptibility gene for Chinese patients with sporadic keratoconus, we performed sequence screening of this gene in such patients. Methods: Whole DNA was obtained from the leukocytes in the peripheral venous blood of 50 patients with sporadic keratoconus and 50 control subjects without this ocular disorder. Polymerase chain reaction single-strand conformation polymorphism analysis and direct DNA sequencing technology were used to detect sequence variation in the five exons and splicing regions of the introns of the VSX1 gene. The sequencing results were analyzed using DNAstar software. Results: One novel missense heterozygous sequence variant (p.Arg131Pro) was found in the first exon of the VSX1 gene in one keratoconus patient. Another heterozygous sequence variant (p.Gly160Val) in the second exon was found in two keratoconus patients. These variants were not detected in the control subjects. In the third intron of the VSX1 gene, c.8326G > A nucleotide substitution (including heterozygous and homozygous change) was also discovered. The frequency of this variation did not differ significantly between patients and controls, it should belong to single-nucleotide polymorphism of the VSX1 gene. Bioinformatic analysis also predicted that one missense sequence variation (p.Arg131Pro) may not cause a pathogenic change. Conclusions: In this study, we added one novel missense sequence variation (p.Arg131Pro) in the coding region of the VSX1 gene to the range of VSX1 coding region variations observed in patients with sporadic keratoconus from China. Our work suggests that VSX1 sequence variants might be involved in the pathogenesis of sporadic keratoconus, but their precise role in disease causation requires further investigation. Keywords: Sporadic keratoconus, VSX1 gene, Sequence variant, Single-nucleotide polymorphism Background [3, 4]. The pathological features of keratoconus include Keratoconus is a congenital disease involving noninflam- decreased corneal collagen or the abnormal distribution matory corneal ectasia. Its prevalence is estimated to be of collagen fiber, which reduce the mechanical resistance 1/2000 in the general population, and the incidence ratio of the cornea and therefore cause the center of the between males and females is 1.7:1 [1, 2]. Although most cornea to protrude, leading to a thin conical shape. Slit keratoconus cases are sporadic, about 6–10% of cases lamp microscope examinations of keratoconus patients have been reported to have a positive family history. have demonstrated Vogt’s line, Fleischer’s ring, and cor- Keratoconus can exhibit dominant or recessive inherit- neal scarring [5–7]. The onset of the disease occurs during ance; with autosomal dominant inheritance, the disease puberty, involving both eyes, and with highly irregular exhibits variable phenotypes with incomplete penetrance astigmatism. In the late phase, patients show acute corneal edema and scar formation, along with significant vision * Correspondence: [email protected] loss. Although several treatment modalities are available, †Equal contributors 3 severe keratoconus remains an indication for corneal Department of Ophthalmology, Sir Run Run Shaw Hospital, Zhejiang – University School of Medicine, Hangzhou 310016, China transplantation [8 10]. Full list of author information is available at the end of the article © The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Guan et al. BMC Ophthalmology (2017) 17:173 Page 2 of 7 Genome-wide linkage analyses have identified several members and identifying the patient as an isolated case chromosomal loci and genes that may be related to kera- of keratoconus. Another 50 healthy people who under- toconus; some of these were eventually ruled out, while went detailed ocular and ophthalmological examinations for others, an association with this disease could not be that ruled out any ophthalmic diseases were selected as confirmed. One of the candidate genes strongly impli- a control group to determine whether the detected vari- cated in keratoconus is visual system homeobox gene 1 ation was SNP of VSX1 gene. The control subjects in- (VSX1) localized to chromosome 20 p11–q11 [11–14]. cluded 31 males and 19 females, aged from 20 to The VSX1 gene encodes a paired-like homeodomain 36 years old. The age and gender generally matched be- transcription factor. It is associated with eye develop- tween the two groups and systemic physical examina- ment and was first isolated and cloned from a cDNA li- tions were performed in both groups to rule out other brary of the retina of adult goldfish. In the human body, concurrent diseases. This study followed the Declaration the VSX1 gene is expressed in the embryonic craniofa- of Helsinki and was reviewed by the ethics committee of cial region, the granular layer of adult retina, and corneal Taizhou Municipal Hospital. Written informed consent tissue. The human VSX1 gene has five exons and en- was obtained from all of the subjects in this study. codes a 365-amino-acid protein with a homeobox DNA binding domain and a CVC domain, being highly con- Genetic study served among vertebrates. Barbaco et al. [15] reported Three milliliters of peripheral venous blood was ex- that the VSX1 gene was activated in corneal stroma dur- tracted from the subjects and stored in EDTA anticoagu- ing the process of corneal wound repair in vitro and in lation tubes. Genomic DNA was isolated from blood vivo, accompanied by the transformation of corneal stro- leukocytes using the Dzup (Blood) Genomic DNA Isola- mal cells into myofibroblasts. These results implied that tion Reagent (B518205; Sangon Biotech Co., Ltd., Shang- VSX1 gene variants may play an important role in the hai, China), in accordance with the manufacturer’s development of keratoconus. Several variants of the standard methods. VSX1 gene [16–19] have been reported from various Based on previous studies [20, 21] and the DNA se- parts of the world, but a definitive pathogenic role of quence of the human VSX1 gene from the NCBI data- these variants in keratoconus has not yet been estab- base, primers were designed for the five exons of this lished because segregation of these variants was also gene. These primers were synthesized by Sangon Biotech seen in some unaffected individuals. Co., Ltd. (Shanghai, China). Sequences of the primers To our knowledge, this is the first study to perform are listed in Table 1. screening for variants of the VSX1 gene in the Chinese The HBP 220 PCR cycler (HYBAID, England) was population and to explore their role in keratoconus. used for a 50-μL PCR reaction system containing 200 ng Nucleotide variations in the five exons and the splicing of DNA template, 5 μL of 10× buffer solution, regions of introns of the VSX1 gene were examined by 1.5 mmol/L MgCl2, 0.25 μmol/L primers, 100 μmol/L of polymerase chain reaction single-strand conformation each dNTP, and 2 U of Taq DNA polymerase (Sangon polymorphism (PCR-SSCP) analysis and direct DNA se- Biotech Co., Ltd., Shanghai, China). The PCR procedure quencing in 50 Chinese patients with keratoconus, was as follows: 94 °C for 5 min; 35 amplification cycles which were compared with the sequences in 50 controls. of denaturation at 94 °C for 45 s, annealing for 45 s, and extension at 72 °C for 50 s; and finally extension at 72 ° Methods C for 10 min. PCR products were examined by 2% agar- Subjects and clinical examination ose gel electrophoresis and EB (Ethidium Bromide) All sporadic keratoconus patients and control subjects staining. The annealing temperatures of each exon and were identified at the Department of Ophthalmology, the fragment sizes of PCR products are listed in Table 1. Taizhou Municipal Hospital. A total of 50 patients were An 8% (49:1) nondenaturing polyacrylamide gel with diagnosed with sporadic keratoconus during the period 5% glycerol was used for SSCP analysis and silver stain- of March 2013 to July 2015, including 29 males and 21 ing. Here, 5-μL PCR products mixed with sample buffer females, aged from 15 to 35 years old. The diagnosis was (90% formamide, 0.05% bromophenol blue, and 0.05% based on symptoms and the results of slit lamp micro- xylene blue) were processed for denaturation at 95 °C scope examinations; the diagnostic features included for 10 min, placed in an ice bath, and then subjected to progressive curvature of the anterior corneal surface electrophoresis (100 V) at room temperature for 5 to steepening, corneal thinning in the same region, 6 h (when xylene blue reached the bottom of the gel). Fleischer’s ring, and Vogt’s stripes, combined with the Then, the gel was fixed in 10% ethanol for 5 min and corneal surface topography and a caudal surface of the soaked in 1% silver nitrate for 5 min, followed by stain- cornea thicker than 20 μm. Patients were considered as ing in 0.012 mol/L silver nitrate and 0.05% formaldehyde sporadic cases after examining the immediate family for 10 min.
Recommended publications
  • The Title of the Dissertation
    UNIVERSITY OF CALIFORNIA SAN DIEGO Novel network-based integrated analyses of multi-omics data reveal new insights into CD8+ T cell differentiation and mouse embryogenesis A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Bioinformatics and Systems Biology by Kai Zhang Committee in charge: Professor Wei Wang, Chair Professor Pavel Arkadjevich Pevzner, Co-Chair Professor Vineet Bafna Professor Cornelis Murre Professor Bing Ren 2018 Copyright Kai Zhang, 2018 All rights reserved. The dissertation of Kai Zhang is approved, and it is accept- able in quality and form for publication on microfilm and electronically: Co-Chair Chair University of California San Diego 2018 iii EPIGRAPH The only true wisdom is in knowing you know nothing. —Socrates iv TABLE OF CONTENTS Signature Page ....................................... iii Epigraph ........................................... iv Table of Contents ...................................... v List of Figures ........................................ viii List of Tables ........................................ ix Acknowledgements ..................................... x Vita ............................................. xi Abstract of the Dissertation ................................. xii Chapter 1 General introduction ............................ 1 1.1 The applications of graph theory in bioinformatics ......... 1 1.2 Leveraging graphs to conduct integrated analyses .......... 4 1.3 References .............................. 6 Chapter 2 Systematic
    [Show full text]
  • VSX1 Mutational Analysis in a Series of Italian Patients Affected by Keratoconus: Detection of a Novel Mutation
    VSX1 Mutational Analysis in a Series of Italian Patients Affected by Keratoconus: Detection of a Novel Mutation Luigi Bisceglia,1 Marilena Ciaschetti,2 Patrizia De Bonis,1 Pablo Alberto Perafan Campo,2 Costantina Pizzicoli,3 Costanza Scala,1 Michele Grifa,1 Pio Ciavarella,1 Nicola Delle Noci,3 Filippo Vaira,4 Claudio Macaluso,5 and Leopoldo Zelante1 PURPOSE. Keratoconus is a noninflammatory corneal disorder Most cases of keratoconus appear to be sporadic, but a that is clinically and genetically heterogeneous. Mutations in positive family history has been documented in 6% to 10% of the VSX1 (visual system homeobox 1) gene have been identi- patients.5 Both recessive and dominant patterns of inheritance fied for two distinct, inherited corneal dystrophies: posterior have been described.6–8 Autosomal dominant inheritance has polymorphous corneal dystrophy and keratoconus. To evalu- more frequently been reported in families, showing incom- ate the possible role of the VSX1 gene in a series of Italian plete penetrance and variable expressivity. Subtle videokerato- patients, 80 keratoconus-affected subjects were screened for graphic anomalies have been reported among relatives of pa- mutations. tients with keratoconus, allowing the detection of low- ETHODS expressivity forms of keratoconus, usually referred to as M . The diagnosis of keratoconus was made on the basis 9–11 of clinical examination and corneal topography. The whole subclinical or forme fruste keratoconus. Multifactorial in- heritance and a major gene model have also been pro- coding region and the exon–intron junctions of the VSX1 gene 12,13 were analyzed by direct sequencing. posed. In some cases nongenetic causes have been postu- lated, such as eye rubbing or rigid contact lens wear, which RESULTS.
    [Show full text]
  • Whole Exome Sequencing in Families at High Risk for Hodgkin Lymphoma: Identification of a Predisposing Mutation in the KDR Gene
    Hodgkin Lymphoma SUPPLEMENTARY APPENDIX Whole exome sequencing in families at high risk for Hodgkin lymphoma: identification of a predisposing mutation in the KDR gene Melissa Rotunno, 1 Mary L. McMaster, 1 Joseph Boland, 2 Sara Bass, 2 Xijun Zhang, 2 Laurie Burdett, 2 Belynda Hicks, 2 Sarangan Ravichandran, 3 Brian T. Luke, 3 Meredith Yeager, 2 Laura Fontaine, 4 Paula L. Hyland, 1 Alisa M. Goldstein, 1 NCI DCEG Cancer Sequencing Working Group, NCI DCEG Cancer Genomics Research Laboratory, Stephen J. Chanock, 5 Neil E. Caporaso, 1 Margaret A. Tucker, 6 and Lynn R. Goldin 1 1Genetic Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Bethesda, MD; 2Cancer Genomics Research Laboratory, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Bethesda, MD; 3Ad - vanced Biomedical Computing Center, Leidos Biomedical Research Inc.; Frederick National Laboratory for Cancer Research, Frederick, MD; 4Westat, Inc., Rockville MD; 5Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Bethesda, MD; and 6Human Genetics Program, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Bethesda, MD, USA ©2016 Ferrata Storti Foundation. This is an open-access paper. doi:10.3324/haematol.2015.135475 Received: August 19, 2015. Accepted: January 7, 2016. Pre-published: June 13, 2016. Correspondence: [email protected] Supplemental Author Information: NCI DCEG Cancer Sequencing Working Group: Mark H. Greene, Allan Hildesheim, Nan Hu, Maria Theresa Landi, Jennifer Loud, Phuong Mai, Lisa Mirabello, Lindsay Morton, Dilys Parry, Anand Pathak, Douglas R. Stewart, Philip R. Taylor, Geoffrey S. Tobias, Xiaohong R. Yang, Guoqin Yu NCI DCEG Cancer Genomics Research Laboratory: Salma Chowdhury, Michael Cullen, Casey Dagnall, Herbert Higson, Amy A.
    [Show full text]
  • Mouse Mutants As Models for Congenital Retinal Disorders
    Experimental Eye Research 81 (2005) 503–512 www.elsevier.com/locate/yexer Review Mouse mutants as models for congenital retinal disorders Claudia Dalke*, Jochen Graw GSF-National Research Center for Environment and Health, Institute of Developmental Genetics, D-85764 Neuherberg, Germany Received 1 February 2005; accepted in revised form 1 June 2005 Available online 18 July 2005 Abstract Animal models provide a valuable tool for investigating the genetic basis and the pathophysiology of human diseases, and to evaluate therapeutic treatments. To study congenital retinal disorders, mouse mutants have become the most important model organism. Here we review some mouse models, which are related to hereditary disorders (mostly congenital) including retinitis pigmentosa, Leber’s congenital amaurosis, macular disorders and optic atrophy. q 2005 Elsevier Ltd. All rights reserved. Keywords: animal model; retina; mouse; gene mutation; retinal degeneration 1. Introduction Although mouse models are a good tool to investigate retinal disorders, one should keep in mind that the mouse Mice suffering from hereditary eye defects (and in retina is somehow different from a human retina, particular from retinal degenerations) have been collected particularly with respect to the number and distribution of since decades (Keeler, 1924). They allow the study of the photoreceptor cells. The mouse as a nocturnal animal molecular and histological development of retinal degener- has a retina dominated by rods; in contrast, cones are small ations and to characterize the genetic basis underlying in size and represent only 3–5% of the photoreceptors. Mice retinal dysfunction and degeneration. The recent progress of do not form cone-rich areas like the human fovea.
    [Show full text]
  • Human Induced Pluripotent Stem Cell–Derived Podocytes Mature Into Vascularized Glomeruli Upon Experimental Transplantation
    BASIC RESEARCH www.jasn.org Human Induced Pluripotent Stem Cell–Derived Podocytes Mature into Vascularized Glomeruli upon Experimental Transplantation † Sazia Sharmin,* Atsuhiro Taguchi,* Yusuke Kaku,* Yasuhiro Yoshimura,* Tomoko Ohmori,* ‡ † ‡ Tetsushi Sakuma, Masashi Mukoyama, Takashi Yamamoto, Hidetake Kurihara,§ and | Ryuichi Nishinakamura* *Department of Kidney Development, Institute of Molecular Embryology and Genetics, and †Department of Nephrology, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan; ‡Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Hiroshima, Japan; §Division of Anatomy, Juntendo University School of Medicine, Tokyo, Japan; and |Japan Science and Technology Agency, CREST, Kumamoto, Japan ABSTRACT Glomerular podocytes express proteins, such as nephrin, that constitute the slit diaphragm, thereby contributing to the filtration process in the kidney. Glomerular development has been analyzed mainly in mice, whereas analysis of human kidney development has been minimal because of limited access to embryonic kidneys. We previously reported the induction of three-dimensional primordial glomeruli from human induced pluripotent stem (iPS) cells. Here, using transcription activator–like effector nuclease-mediated homologous recombination, we generated human iPS cell lines that express green fluorescent protein (GFP) in the NPHS1 locus, which encodes nephrin, and we show that GFP expression facilitated accurate visualization of nephrin-positive podocyte formation in
    [Show full text]
  • Differentiation of Human Embryonic Stem Cells Into Cone Photoreceptors
    © 2015. Published by The Company of Biologists Ltd | Development (2015) 142, 3294-3306 doi:10.1242/dev.125385 RESEARCH ARTICLE STEM CELLS AND REGENERATION Differentiation of human embryonic stem cells into cone photoreceptors through simultaneous inhibition of BMP, TGFβ and Wnt signaling Shufeng Zhou1,*, Anthony Flamier1,*, Mohamed Abdouh1, Nicolas Tétreault1, Andrea Barabino1, Shashi Wadhwa2 and Gilbert Bernier1,3,4,‡ ABSTRACT replacement therapy may stop disease progression or restore visual Cone photoreceptors are required for color discrimination and high- function. However, a reliable and abundant source of human cone resolution central vision and are lost in macular degenerations, cone photoreceptors is not currently available. This limitation may be and cone/rod dystrophies. Cone transplantation could represent a overcome using embryonic stem cells (ESCs). ESCs originate from therapeutic solution. However, an abundant source of human cones the inner cell mass of the blastocyst and represent the most primitive remains difficult to obtain. Work performed in model organisms stem cells. Human ESCs (hESCs) can develop into cells and tissues suggests that anterior neural cell fate is induced ‘by default’ if BMP, of the three primary germ layers and be expanded indefinitely TGFβ and Wnt activities are blocked, and that photoreceptor genesis (Reubinoff et al., 2000; Thomson et al., 1998). operates through an S-cone default pathway. We report here that Work performed in amphibians and chick suggests that primordial Coco (Dand5), a member of the Cerberus gene family, is expressed cells adopt a neural fate in the absence of alternative cues (Muñoz- in the developing and adult mouse retina. Upon exposure Sanjuán and Brivanlou, 2002).
    [Show full text]
  • A Three-Dimensional Organoid Model Recapitulates Tumorigenic Aspects
    www.nature.com/scientificreports OPEN A three-dimensional organoid model recapitulates tumorigenic aspects and drug responses of Received: 22 June 2018 Accepted: 10 October 2018 advanced human retinoblastoma Published: xx xx xxxx Duangporn Saengwimol1, Duangnate Rojanaporn2, Vijender Chaitankar3, Pamorn Chittavanich4, Rangsima Aroonroch5, Tatpong Boontawon4, Weerin Thammachote4, Natini Jinawath4, Suradej Hongeng6 & Rossukon Kaewkhaw4 Persistent or recurrent retinoblastoma (RB) is associated with the presence of vitreous or/and subretinal seeds in advanced RB and represents a major cause of therapeutic failure. This necessitates the development of novel therapies and thus requires a model of advanced RB for testing candidate therapeutics. To this aim, we established and characterized a three-dimensional, self-organizing organoid model derived from chemotherapy-naïve tumors. The responses of organoids to drugs were determined and compared to relate organoid model to advanced RB, in terms of drug sensitivities. We found that organoids had histological features resembling retinal tumors and seeds and retained DNA copy-number alterations as well as gene and protein expression of the parental tissue. Cone signal circuitry (M/L+ cells) and glial tumor microenvironment (GFAP+ cells) were primarily present in organoids. Topotecan alone or the combined drug regimen of topotecan and melphalan efectively targeted proliferative tumor cones (RXRγ+ Ki67+) in organoids after 24-h drug exposure, blocking mitotic entry. In contrast, methotrexate showed the least efcacy against tumor cells. The drug responses of organoids were consistent with those of tumor cells in advanced disease. Patient-derived organoids enable the creation of a faithful model to use in examining novel therapeutics for RB. Retinoblastoma (RB) is a serious childhood retinal tumor that, if lef untreated, can cause death within 1–2 years.
    [Show full text]
  • Characterization of Human-Ipscs Derived Spinal Motor Neurons by Single
    bioRxiv preprint doi: https://doi.org/10.1101/2019.12.28.889972; this version posted December 28, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Characterization of human-iPSCs derived spinal motor neurons by single- cell RNA sequencing Louise Thiry1, Regan Hamel2, Stefano Pluchino2, Thomas Durcan1,3, Stefano Stifani1* 1Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, 3801, rue University, Montreal (Quebec) H3A 2B4, Canada 2Department of Clinical Neurosciences, Clifford Allbutt Building - Cambridge Biosciences Campus and NIHR Biomedical Research Centre, University of Cambridge, Hills Road, CB2 0HA Cambridge, UK 3Early Drug Discovery Unit, Montreal Neurological Institute-Hospital *Corresponding author: [email protected] 1 bioRxiv preprint doi: https://doi.org/10.1101/2019.12.28.889972; this version posted December 28, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Abstract Human induced pluripotent stem cells (iPSCs) offer the opportunity to generate specific cell types from healthy and diseased individuals, allowing the study of mechanisms of early human development, modelling a variety of human diseases, and facilitating the development of new therapeutics. Human iPSC-based applications are often limited by the variability among iPSC lines originating from a single donor, as well as the heterogeneity among specific cell types that can be derived from iPSCs. The ability to deeply phenotype different iPSC-derived cell types is therefore of primary importance to the successful and informative application of this technology.
    [Show full text]
  • Zygotic Vsx1 Plays a Key Role in Defining V2a Interneuron Sub
    International Journal of Molecular Sciences Article Zygotic Vsx1 Plays a Key Role in Defining V2a Interneuron Sub-Lineage by Directly Repressing tal1 Transcription in Zebrafish Qi Zhang 1 , Haomang Xu 1, Wei Zhao 1, Jianbo Zheng 1,2 , Lei Sun 1 and Chen Luo 1,* 1 College of Life Sciences, Zhejiang University, Hangzhou 310058, China; [email protected] (Q.Z.); [email protected] (H.X.); [email protected] (W.Z.); [email protected] (J.Z.); [email protected] (L.S.) 2 Zhejiang Institute of Freshwater Fisheries, Huzhou 313001, China * Correspondence: [email protected] Received: 18 April 2020; Accepted: 15 May 2020; Published: 20 May 2020 Abstract: In the spinal cord, excitatory V2a and inhibitory V2b interneurons are produced together by the final division of common P2 progenitors. During V2a and V2b diversification, Tal1 is necessary and sufficient to promote V2b differentiation and Vsx2 suppresses the expression of motor neuron genes to consolidate V2a interneuron identity. The expression program of Tal1 is triggered by a Foxn4-driven regulatory network in the common P2 progenitors. Why the expression of Tal1 is inhibited in V2a interneurons at the onset of V2a and V2b sub-lineage diversification remains unclear. Since transcription repressor Vsx1 is expressed in the P2 progenitors and newborn V2a cells in zebrafish, we investigated the role of Vsx1 in V2a fate specification during V2a and V2b interneuron diversification in this species by loss and gain-of-function experiments. In vsx1 knockdown embryos or knockout Go chimeric embryos, tal1 was ectopically expressed in the presumptive V2a cells, while the generation of V2a interneurons was significantly suppressed.
    [Show full text]
  • Transdifferentiation of the Retina Into Pigmented Cells in Ocular Retardation Mice Defines a New Function of the Homeodomain Gene Chx10 Sheldon Rowan1, C.-M
    Research article 5139 Transdifferentiation of the retina into pigmented cells in ocular retardation mice defines a new function of the homeodomain gene Chx10 Sheldon Rowan1, C.-M. Amy Chen1,*, Tracy L. Young1, David E. Fisher2 and Constance L. Cepko1,† 1Department of Genetics and Howard Hughes Medical Institute, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA 2Department of Pediatric Oncology, Dana Farber Cancer Institute, 44 Binney Street, Boston, MA 02115, USA *Present address: Hydra Biosciences, 790 Memorial Drive, Suite 203, Cambridge, MA, 02139, USA †Author for correspondence (e-mail: [email protected]) Accepted 10 June 2004 Development 131, 5139-5152 Published by The Company of Biologists 2004 doi:10.1242/dev.01300 Summary The homeodomain transcription factor Chx10 is one of the normally found only in the periphery into central regions earliest markers of the developing retina. It is required for of the eye. These genes included a transcription factor retinal progenitor cell proliferation as well as formation of controlling pigmentation, Mitf, and the related factor Tfec bipolar cells, a type of retinal interneuron. orJ (ocular (Tcfec – Mouse Genome Informatics), which can activate a retardation) mice, which are Chx10 null mutants, are melanogenic gene expression program. Misexpression of microphthalmic and show expanded and abnormal Chx10 in the developing retinal pigmented epithelium peripheral structures, including the ciliary body. We show (RPE) caused downregulation of Mitf, Tfec, and associated here, in a mixed genetic background, the progressive pigment markers, leading to a nonpigmented RPE. These appearance of pigmented cells in the neural retina, data link Chx10 and Mitf to maintenance of the neural concomitant with loss of expression of retinal markers.
    [Show full text]
  • Gene Expression Profiling Identifies Different Sub-Types of Retinoblastoma', British Journal of Cancer, Vol
    University of Birmingham Gene expression profiling identifies different sub- types of retinoblastoma Kapatai, G.; Brundler, M. A.; Jenkinson, H.; Kearns, P.; Parulekar, M.; Peet, A. C.; McConville, C. M. DOI: 10.1038/bjc.2013.283 Document Version Publisher's PDF, also known as Version of record Citation for published version (Harvard): Kapatai, G, Brundler, MA, Jenkinson, H, Kearns, P, Parulekar, M, Peet, AC & McConville, CM 2013, 'Gene expression profiling identifies different sub-types of retinoblastoma', British Journal of Cancer, vol. 109, no. 2, pp. 512-525. https://doi.org/10.1038/bjc.2013.283 Link to publication on Research at Birmingham portal Publisher Rights Statement: This work is published under the standard license to publish agree- ment. After 12 months the work will become freely available and the license terms will switch to a Creative Commons Attribution- NonCommercial-Share Alike 3.0 Unported License. General rights Unless a licence is specified above, all rights (including copyright and moral rights) in this document are retained by the authors and/or the copyright holders. The express permission of the copyright holder must be obtained for any use of this material other than for purposes permitted by law. •Users may freely distribute the URL that is used to identify this publication. •Users may download and/or print one copy of the publication from the University of Birmingham research portal for the purpose of private study or non-commercial research. •User may use extracts from the document in line with the concept of ‘fair dealing’ under the Copyright, Designs and Patents Act 1988 (?) •Users may not further distribute the material nor use it for the purposes of commercial gain.
    [Show full text]
  • Expression and Function of ZEB1 in the Cornea
    cells Review Expression and Function of ZEB1 in the Cornea Yingnan Zhang 1,2,†, Xiao Liu 3,†, Wei Liang 4, Douglas C. Dean 1,2,5, Lijun Zhang 4,* and Yongqing Liu 1,2,5,* 1 Department of Medicine, University of Louisville School of Medicine, Louisville, KY 40202, USA; [email protected] (Y.Z.); [email protected] (D.C.D.) 2 James Brown Cancer Center, University of Louisville School of Medicine, Louisville, KY 40202, USA 3 Department of Ophthalmology, The Second Xiangya Hospital of Central South China University, Changsha 410011, China; [email protected] 4 Department of Ophthalmology, The Third People’s Hospital of Dalian, Dalian Medical University, Dalian 116033, China; [email protected] 5 Birth Defects Center, University of Louisville School of Dentistry, Louisville, KY 40202, USA * Correspondence: [email protected] (L.Z.); [email protected] (Y.L.); Tel.: +86-181-4117-8066 (L.Z.); +1-502-852-8669 (Y.L.) † Y.Z. and X.L. contribute equally. Abstract: ZEB1 is an important transcription factor for epithelial to mesenchymal transition (EMT) and in the regulation of cell differentiation and transformation. In the cornea, ZEB1 presents in all three layers: the epithelium, the stroma and the endothelium. Mutations of ZEB1 have been linked to multiple corneal genetic defects, particularly to the corneal dystrophies including keratoconus (KD), Fuchs endothelial corneal dystrophy (FECD), and posterior polymorphous corneal dystrophy (PPCD). Accumulating evidence indicates that dysfunction of ZEB1 may affect corneal stem cell homeostasis, and cause corneal cell apoptosis, stromal fibrosis, angiogenesis, squamous metaplasia. Understanding how ZEB1 regulates the initiation and progression of these disorders will help us in Citation: Zhang, Y.; Liu, X.; Liang, targeting ZEB1 for potential avenues to generate therapeutics to treat various ZEB1-related disorders.
    [Show full text]